Shell mold multiple pump system



May 16, 1961 R. H, MOORE 2,984,390

SHELL MOLD MULTIPLE PUMP SYSTEM Filed Nov. 14, y1958 4 Sheets-Sheet 1 EQF2-l NQE'NQOR RUSSELL H MOORE glas-.5 Shk ATTORNEY May 16, 1961 R, L..MOORE 2,984,390

SHELL MOLD MULTIPLE PUMP SYSTEM Filed Nov. 14, 1958 4 Sheets-Sheet 2y-v-i 17-2,

/NVE/v TGR I@USSL-"LL H. MOO/QE BY (J, may 627mm* AWRNEY May 16, 1961 R.H. MOORE 2,984,390

SHELL MOLD MULTIPLE PUMP SYSTEM Filed Nov. 14, 1958 4 Sheets-Sheet 3 lll1^/ VEA/TOR RUSSELL A400/QE BYCJGGASWJQHH ATTORNEY May 16, 1961 R. HMOORE SHELL MOLD MULTIPLE PUMP SYSTEM 4 Sheds-Sheet 4 Filed Nov. 14,1958 A TTORNE Yl ritited States Patent@ SHELL MOLD MULTIPLE PUMP SYSTEMRussell H. Moore, Gladstone, Va., assignor to Lynchburg Foundry Company,Lynchburg, Va., a corporation of Virginia Filed Nov. 14, 1958, Ser. No.773,983

2 Claims. (Cl. 222-255) The present invention relates to metal casting,by means of shell molds, particularly method and means for gluingtogether superposed shell mold sections.

In the prior art various means have been employed for joining or gluingtogether shell mold sections. Conventionally, such sections are joinedby the application of a dry or liquid thermosetting resin component tollat surfaces of one of two halves of a shell mold and thereaftercompressing the same together. Some systems include the utilization ofcorresponding tongue and groove in mold sections; however, there has notbeen provided satisfactory means for conveying a uniform quantity ofglue into such depressions.

As a result of these shortcomings there involves, quite often, thedeposit of either too much or too little glue on the shell. When toomuch glue is deposited it separates the two halves of the shell moldthereby increasing the parting line dimensions of the resultant casting.This increased parting line dimension will make the casting dimentionbeyond tolerance and the result is a scrapped casting. When too littleglue is deposited the two shell halves do not adhere satisfactorily andeither the shell mold must be scrapped or if metal is poured into suchshell molds the castings are lost. Also when it is necessary to applydry thermosetting resin near the mold cavities the dry powder tends todrift into the cavities and causes poor casting finish.

All of the above shortcomings are overcome by the instant mutiple pumpsystem, wherein a given quantity of glue is deposited into a pluralityof strategically placed depressions in one half of the shell mold, withthe other half of the shell mold having a corresponding boss for eachdepression and clearance is provided between each depression and eachboss to prevent any glue from coming onto the hat surfaces of the shellhalves but still gluing the two halves of the shell mold firmlytogether.

Another shortcoming of prior art systems resides in the use of templatesfor holding the glue pump applicators. Of necessity, these have beentailored individually in size and conformation to the shell moldsections being glued together. As a result, much time and money has beenlost in developing complete separate templates and glue reservoirs foreach sheld mold application. Additionally, the great time and effortrequired to clean and replace these templates is a problem whichadversely affects the productivity per capita.

According to the present invention, a plurality of pumps are selectivelypositioned within a permanent glue reservoir. Flexible outlets leadrespectively from said pumps and are removably disposed with respect tothe surfaces being glued by a suitable and inexpenisve template. Thetemplate or glue dispensing tube guide does not serve simultaneously asa glue reservoir and hence it is not soiled during each use. Outlet gluedispensing tubes not required during a particular application may beinserted in suitable openings atop the pressure plate so that gluepumped therethrough is simultaneously returned to the reservoir. Checkvalve and spring retarding means in each of said pumps insure that apartial vacuum is maintained in the outlets during non-pumping and thusunscheduled dripping of glue is prevented. As a result, accuratelymeasured quantities of glue may be deposited upon the selected shellmold half or section having suitable depressions or grooves for gluedeposit,

Accordingly, it is an object of invention to provide a shell mold gluingsystem, means for accurately depositing measured quantities of .liquidglue upon shell mold sections.

Another object is to provide in shell mold sections recesses or groovesfor holding glue and corresponding bosses or tongues partially fittinginto such recessesY to sealingly join mating shell mold sections withoutdeposit ing glue on the flat surfaces of said shell :mold sections.

An additional object of invention is to provide a liquid dispensingshell mold gluing system which is substantially universally adaptable tovarious shell mold section designs.

Additional objects of invention will become apparent from the foregoingpreamble and ensuing description and attached drawings wherein likenumbers designate like elements.

Figure l is a side elevational view partially in fragment of a multiplepump shell mold system in accordance with the invention .applying glueto a supported shell mold section;

Figure 2 is a sectional view taken along section line 2 2 of Figure l,showing a plurality of pumps mounted in a glue reservoir with overheadpressure plate abutting plungers of said pumps;

Figure 3 is an enlarged sectional view of one form of glue pump showingplunger and valving means positioned within the pump cylinder; and

Figure 4 is an enlarged phantom section view of the joining of shellmold sections by glue means adhering to corresponding portions of gluerecesses and bosses; and

Figure 5 is a rnodied glue pump assembly in side elevation, partiallyfragmentary.

In Figure l, glue reservoir 18 is illustrated as mounted upon laterallyadjustable frame 10 by means of transverse supports 38 and braces 46.Frame 10 is mounted upon yoke 40 which is pivoted upon upright bolt 42in support 44. Pressure plate 14 adjustably covers reservoir 1S and isvertically actuable by means of piston system 12, the same beingattached to frame 10 by means of bolts 50. interconnecting piston 12 andpressure plate 14 is a steel cylinder rod which lits into rod end ange32. For access to reservoir 18, removable side plate 16 is employed.Adjusting bolts 34 are provided at either side of pressure plate 14.During the downward thrust of pressure plate 14, bolts 34 strikeabutments 36 which are suitably welded to angle bar supports 38. Gluefiller spout 20 is provided at the front of the reservoir 18. In Figurel the liquid glue shell mold pumps, generally designated as 22, areshown as removably interconnecting glue reservoir 18 and template 24.

In Figure 1 shell mold section 26 having glue recess 80 is shown assupported upon support plate 4S having common projections 28. See alsoFigure 4. Springs 30 encircling upright members 2S provide desiredupward pressure, forcing a lower shell mold half against its uppercounterpart to seal the respective halves together. A correspondingassembly, not shown, engages the upper half of the mold in actualpractice. Template 24 may consist of 1736 inch steel metal and may haveas many as 64 apertures which correspond to the 64 outlets provided inthe presently used shell mold reservoir assembly 18 with adapters.However, the invention is: not to be thus limited as it will be apparentto those skilled in the art that any number of geometrically disposedapertures may be provided.

As shown in Figures 2 and 3, pump .22 consists of upright cylinder 58,housing the plunger 56. This plunger is urged upwardly by spring 34principally. Cylinder 58 is positioned in the outlet holes 54 of thereservoir bottom so that cylinder apertures are .substantially adjacentthe bottom of glue reservoir 18. Thus, tirst use of the oldest glue inthe reservoir is insured, the glue concentrates being first availablefor pumping. This is a principal distinction over other gluing pumpswherein intake apertures are disposed well above the bottom of the oldpan-type reservoir. Threadedly engaging the bottom of cylinder 58 isball check valve housing 62. Ball check valve 64 seats upwardly againstcylinder 58 and moves vertically between valve seat and the top ofcoupling 72. Check valve spring 66 urges the ball check valve towardshoulder 70 and override spring 68 retards the return movement of theball check valve to its seat 70. In pumping, valve 64 will often restatop coupling 72 in which Vslots 71 permit liquid glue flow into the`coupling interior. Delay of the seating of the ball check valve on itsupper and only valve seat insures that a portion of the total gluevolume in the flexible tube nozzle outlet 78 is retained therein asagainst dripping upon Completion of a measured deposit. A vacuum is thusinsured in each flexible tube 74 to the extent that glue is removed fromthe lower nozzle outlet 78 and dripping is positively prevented.

Threadedly engaging the ball check housing 62 is tube coupling 72. Asshown in Figure 2, flexible tube 74 is connected to coupling 72 and hasnozzle outlet 78 at its lower end. Swivel nut 76 is providedintermediately t0 removably engage template 24. As indicated by Figure1, nozzles 78 which are not required during a particular application,may be inserted in suitable openings atop the pressure plate so thatglue pumped through idle .tubes is simultaneously returned to thereservoir.

As Will be seen in Figure 4, a schematic shell mold section 26 isprovided with a plurality of glue recesses 80; Corresponding shell moldsection 29 adjoined thereto is provided with corresponding bosses 82,the latter partially tting into recesses 80, dissipating the scheduledand measured quantity of glue 52 lwithin recess 80 only and thusavoiding setting up. The measured quantity is obviously determined bythe vertical stroke of pump 22 and this stroke is in turn established byadjustment of bolt 34 with respect to its aligned abutment 36. (SeeFigure l.)

Referring now to Figure 5, wherein a modification of glue dispensing subassembly is depicted, it will be noted that the valve mechanism isdisposed in the template engaging head. Cylinder engages the reservoir18 at its floor through threaded contact. The cylinder includes glueintake apertures 112, opposed to each other and the cylinder housesplunger with return spring 122 being compressed between plunger head andcylinder top. Coupling 124 joins cylinder 110 and fitting 126 to providea base for the flexible `hose 128. At the lower end of Yhose 128 a tting130 ogether with barrel .140 retains magnet 132 in position. The magnetis adapted to secure the dropper 142 to the template which is ofmagnetizable substance. Barrel carries dropper 142 in extension and avalve seat 144 near its top. Check valve 146 seats against the shoulder144 as plunger 120 is released, but upon depression of the plunger thevalve will become unseated permitting fluid to ow as in the previousmodification. Note the by-pass grooves at the top of dropper 142accommodating uid by-pass should the valve seat onto the top of dropper142 by compression of spring 148.

Manlfestly, the present invention may be applied to the measuredapplication of other fluids or liquids to speciiied areas by means ofsuitable templates. 1t is to be understood that the forms of invention,herewith shown and described, are to be taken as a preferred example ofthe same, and that various changes in the shape, size and arrangement ofparts maybe resorted to, without departing from the spirit of invention,or the scope of the subjoined claims.

I claim:

1. A multiple pump system for gluing shell molds comprising a gluereservoir; a vertically adjustable pres,- sure plate, said pressureplate encompassing said reservoir; a multiplicity of glue pumps mountedwithin said reservoir and abutting said pressure plate, each said pumpincluding a cylinder extending through the bottom of said reservoir andhaving an intake aperture within said reservoir for withdrawal of gluethrough said cylinder, a plunger slidably mounted in said cylinderadjacent said aperture, and a spring tensioned ball check valvesupported at the end of said cylinder outside of said reservoir, saidball check valve being closed against a seat in said cylinder by springmeans, whenever said plunger is not pumpingly depressed by verticalactuation of said pressure plate, said ball check valve thus creating apartial vacuum in the outlet of said pump system and flexible outletsattached to each of said ball check valves and spacedly retained attheir respective outlet ends by a template, said outlets beingindividually utilizable so that those not required during a particulargluing application may be attached to said pressure plate for return ofpumped glue to said reservoir during pumping.

2. A multiple pump system as in claim 1, said ball check Valve includingpressure spring override means intermediate said plunger and said valveseat.

References Cited in the le of this patent UNITED STATES PATENTS 765,731Hooton et al. July 26, 1904 921,594 Crane May 11, 1909 1,582,092 StacyApr. 27, 1926 1,637,613 Johnson Aug. 2, 1927 1,698,023 Mathewson a Ian.8, 1929 1,793,978 Ward Feb. 24, 1931 2,296,861 Matter Sept. 29, 19422,312,625 Cathey Mar. 2, 1943 2,597,175 Perkins May 20, 1952 2,670,877Logue Mar. 2, 1954 2,734,667 Conklin Feb. 14, 1956 2,771,225 PerkinsNov. 20, 1956 2,800,931 Sutcliie July 30, 1957 2,902,860 Glass Sept. 8,1959 2,942,622 Hahan et al. June 28, 1960

